1. Field of the Invention
The present invention relates to a line-of-sight-information input apparatus and method. More particularly, the invention relates to a light-of-sight-information input apparatus and method which is suitable for realizing a function as an interactive device between a user and a computer by utilizing line-of-sight information detected by a line-of-sight detection device and transmitting an event message to a graphical user interface displayed on a display device of the computer.
2. Description of the Related Art
Houses and keyboards are typical conventional user interfaces. The user can move a mouse pointer on a window by operating a mouse, or can operate a window application program by clicking or double-clicking a mouse button for a graphical user interface, such as Windows of the Microsoft Corporation, MacIntosh of the Apple Corporation, or X-Window developed by the MIT (Massachusetts Institute of Technology). The user can also input a character which is difficult to input with a mouse, by using a keyboard in addition to the mouse.
In conventional mouse devices, when the user moves a mouse, the OS (operating system) of the computer moves a mouse pointer on a display in accordance with the moved distance of the mouse, in response to a mouse-pointer movement event message sent to the OS of the computer by the mouse. By clicking or double-clicking a mouse button, a mouse-click/double-click event message is transmitted to the OS, which performs an appropriate action for each application program.
In the above-described conventional technique, when utilizing a mouse in a graphical user-interface environment, the user can display a plurality of application programs on a display device of a computer. When the user intends to perform an input operation for one of these application programs, it is necessary that the window of that application program is active (in a state capable of being used). Usually, the window can be made active by moving a mouse pointer to the application window and clicking or double-clicking a mouse button.
In the conventional technique, however, when the user intends to perform an input operation through a keyboard for an application program and then perform an input operation for another application program, it is necessary that the user first releases his hand from the keyboard and then activates the window of the application to be used active by operating a mouse. Such a procedure is inefficient in practice.